Page:Popular Science Monthly Volume 21.djvu/370

358 utilize the borate of lime, in the form of ulexite, for the conversion into borax of the carbonate of soda held in the water of Hachinhama.

The ulexite was brought by car-loads from the deserts east of the Sierra Nevada to San Francisco, and thence to Clear Lake, and a great increase in the borax yield of Hachinhama was the result. The process adopted was to saturate, with the ulexite, the boiling lye from the lixiviating tanks, before it had acquired sufficient strength to crystallize on cooling. A double decomposition was thus accomplished, resulting in a thick, milky-looking mixture which was an intensified solution of borax, rendered turbid by the insoluble carbonate of lime, this latter speedily settling and leaving the clear borax-liquor for concentration and crystallization.

Practically, however, this solution was never pure, for here came in again the same fact which had been demonstrated in the first workings at Hachinhama, that the bulk of the liquid in which the action took place had much to do with the chemical union accomplished. In laboratory experiments the work was perfect, and a boiling-heat of only a few minutes formed the full theoretical amount of borax demanded; yet, when dealing with large quantities, this proved impracticable. Although violent boiling was long continued, even for hours, analysis of the lye showed that a certain proportion of the carbonate of soda still remained untouched by the boracic acid, and that, too, when the ulexite employed was in excess of the amount which careful analysis showed was sufficient to saturate the carbonate of soda present. And this excess was a necessity, and the daily working came to recognize it and to act accordingly, for, when the even theoretical quantity only was used, a much larger proportion of the soda remained untouched.

The operations at Hachinhama continued vigorously till 1874, by which time the enormous supply of borax brought into the market from Nevada had reduced the price to so low a point that further production became impossible. Hachinhama supplied all the American borax made from the cessation of work at Borax Lake in 1868 till 1873, and the two localities afforded between 1864 and 1874 all that was ever made in California. The yield of Hachinhama, during the last two years of its running, was something over 5,000 cases of 112 pounds each.

The immense stock crowding upon the market, which has reduced the price of borax to very nearly one fourth of its former rate, is commonly called "California borax," but that is a misnomer, originating in the fact that it has necessarily been shipped from San Francisco; it is exclusively a product of Nevada. It is, in its look, so unlike the ordinary English borax, or that made at Hachinhama, that the contrast is very striking. Still it is practically the same, and has the same working value.

A glance at the map of the State of Nevada shows a large number